James Balog has spent his career pushing the artistic and adventure boundaries of nature photography. For the past five years, he's been capturing the impact of climate change on glaciers, culminating in the powerful film Chasing Ice. What he documented was catastrophic—and should be required viewing for every policymaker on earth.

“We’ve all skied nasty rain crust before, but this was something else,” James Balog told me when we met up in Ouray, Colorado, in early January 2012. “Absolutely, unbelievably horrible.”

Yesterday, before I arrived, Balog and his field assistant, 29-year-old Matthew Kennedy, skinned off the west side of Red Mountain Pass, just south of Ouray, to download images from a weatherproof time-lapse camera they’d positioned on a ridgetop, at 12,186 feet. Now I’m tagging along as they check on a second high-altitude camera, part of a long-term survey documenting the effects of climate change on hydrology patterns in the American West.

Thankfully, the sun has softened the thin, wind-hammered snowpack, and after an hour of easy skinning we reach Balog’s rig, a modified Nikon D200. It’s sitting inside a hard case with a plexiglass window, bolted in place about halfway up a 20-foot instrument mast—a steel tower festooned with various devices measuring atmospheric conditions. Using a safety harness, Balog climbs the tower’s rungs, swaps out a memory card, and makes sure the custom hardware—which he helped design—is doing its job, directing the camera to snap a picture every 60 minutes during daylight. Kennedy shoots some B-roll of the 60-year-old Balog hanging off the structure, but we don’t linger long. We’ve got other cameras to check on and a dicey descent back to the car.

The two setups, which Balog refers to as dust cameras, are part of a research project he’s working on with scientists at the University of Colorado. When dust from western windstorms settles on snowpack in large amounts—which has been happening with increasing frequency over the past decade—it changes the albedo, or reflectivity, of the snow. The snow absorbs more energy and evaporates faster, causing spring runoff to start one or two months early and reducing overall runoff by five percent—which translates to 800,000 acre-feet of water, more than twice the annual Colorado River water allocation for Las Vegas.

“Which is a big deal,” says Jeffrey Deems, the project’s lead researcher and a scientist with the Cooperative Institute for Research in Environmental Sciences (CIRES), “especially when you consider that the Colorado River system is the foundation of a multibillion-dollar economy and the major water supply for 30 million people in seven states.”

The dust cameras are an outgrowth of Balog’s Extreme Ice Survey, an ongoing project that he launched in 2007 to document the melting of the earth’s great ice sheets. Using 48 time-lapse cameras positioned on 24 glaciers at five major locations—Greenland, Iceland, Nepal, Alaska, and the northern Rocky Mountains—EIS has captured more than a million images to date. Made up of a loose affiliation of photographers, scientists, and volunteers, the survey has resulted in two National Geographic cover stories, a Nova segment, two books, and the feature-length documentary Chasing Ice, which won a cinematography award at Sundance last year and made its theatrical debut in New York City in November. By then the film had won more than 20 awards and been screened at some 50 festivals.

The accolades are nothing new for Balog, who has enjoyed a long and decorated career as an environmental photographer, adventurer, and, most recently, climate-change researcher. His work has been exhibited in more than 100 museums and galleries, and in 1996 he became the first photographer commissioned by the U.S. Postal Service to create a set of stamps, which featured Balog’s signature shots of endangered species. But nothing has resonated quite like the ice images. “The grind of giant glaciers has become one of the undertones of our era, and it’s taken too long for people to viscerally understand the power of climate change,” says Bill McKibben, the author and climate activist. “Balog’s images are finally helping do the trick.”

Chasing Ice was directed by first-timer Jeff Orlowski and produced by Orlowski, Jerry Aronson, and Paula DuPré Pesmen, who won an Oscar for her work on the dolphin-slaughter documentary The Cove. It can be tough to watch; audiences are visibly shaken as miles of glaciers vanish before their eyes. From 2007 to 2010, the Columbia Glacier in Alaska receded so much—two and a half miles—that, on three separate visits, Balog’s team had to move one of its fixed cameras just to keep the glacier in the viewfinder. At Greenland’s Ilulissat Glacier, the team documented the largest iceberg calving ever caught on film. “In 10 years,” Balog says, “it retreated more than it had in the previous 100.”

Getting the images and footage wasn’t easy. As you see in the film, Balog and his team waded into frigid waters in Iceland, clung to ice-rimed rock faces in Alaska, and got battered by wind, snow, and subfreezing temperatures as they fiddled with cameras in some of the harshest environments on the planet. But nothing, including several surgeries to fix Balog’s damaged knees, gets in the way of his obsession to capture the shrinking of the world’s glaciers. “We need to be grown-up enough as artists to look at this stuff with eyes wide open,” he says. “And if audiences can’t take it, too bad.”

A FEW HOURS AFTER our field trip, we hop into Balog’s old Honda Pilot and head to his family’s vacation yurt near Ridgway, the next town over from Ouray. Balog lives with his wife and two daughters in the foothills above Boulder, but the yurt is where they come to unplug. It sits about a quarter of a mile off an unplowed section of dirt road, so we strap on our skis and skin in for the last mile and a half.

If there’s a better view in Colorado, I haven’t seen it. Looking east, a string of thirteeners and fourteeners, including Teakettle Mountain and Mounts Sneffels and Ridgway loom regally in the distance. Closer in, the scene isn’t as pretty. The gently sloping meadow just northeast of the yurt is littered with hundreds of aspens that have died from sudden aspen decline (SAD), which has blighted nearly a fifth of Colorado’s stands. Warmer, drier conditions have severely stressed the trees, leaving them susceptible to pests and fungi. The next hill is even worse.

“All of this was filled with trees in 2002,” Balog says, waving at a large swath of dead timber. Working to document the effects of SAD for a Colorado non-profit called For the Forest, Balog has set up two time-lapse cameras near the yurt. One is taking wide-angle shots of the tips of three growing trees; the second is positioned about a foot from the trunk of a mature aspen. Its bark is cracked, and it’s oozing black stuff out of a wound that Kennedy calls its Eye of Sauron.

At other locations in the Rockies, Balog has set up beetle cams. Since 2000, more than 50 million acres of ponderosa and whitebark pines—an area roughly the size of Kansas—have been harmed or killed by an unprecedented outbreak of bark beetles, which burrow inside and consume the trees’ soft cambium. Sustained cold temperatures are required to kill beetle eggs and keep their populations in check, but the recent spate of warm winters and severe droughts has tipped the balance in favor of the insects.

This die-off has cost the timber industry billions, but the biggest concern is the fuel it’s providing for wildfires. “Many of the trees are just now starting to fall,” says John Bennett, former executive director of For the Forest. “They’re basically a huge pile of kindling on the forest floor.”

Like the dust cameras, the tree and beetle cams are part of Balog’s larger mission to document what he calls “the Anthropocene in action.” Anthropocene means “new man,” and the term was first used in a geological context in 2000, when Paul Crutzen, a Nobel Prize–winning atmospheric chemist from Holland, coined it at a scientific conference. The idea is that the Holocene epoch of geologic time, which began around 12,000 years ago, has ended. Sometime in the past few hundred years, it was supplanted by a new time frame called the Anthropocene. This concept is being looked at seriously by geologists; for it to fully take hold, experts will have to conclude that human activities—like population growth and the burning of fossil fuels—will be clearly discernible in the rock record of the future.

Over the past decade, the notion has gained steam: in 2008, the International Commission on Stratigraphy, the group of scientists who officially determine the time frames of epochs, began reviewing it. The process will likely take years, but for many scientists and climate-change activists the truth is already out there.

“Ice is just the first chapter,” says Dennis Dimick, executive editor for the environment at National Geographic. “The story is much bigger than that. What’s going to happen to the jet stream? Rainfall? To corn, wheat, and soy crops in the Midwest? People will start to pay attention when our entire global food supply is disrupted and the question becomes: What’s for lunch, dude?”

BALOG HAS THE LANKY, craggy look one associates with a seasoned mountaineer, which he is. In the late 1970s, he began scaling peaks in the Alps, the Himalayas, and Alaska, and he was also teaching Outward Bound courses in Colorado. He got serious about photography in the 1980s, while he was in the field earning a master’s in geomorphology, the study of the evolution and configuration of landforms, at the University of Colorado. His interest in earth sciences has informed his work ever since, even though, early in his career, he was not a climate-change believer.

“I had studied ice in graduate school, and I was skeptical of the computer modeling they were using,” says Balog. “I thought, Jesus Christ, they’ve come up with this thing to get people all fired up. I thought it was overblown.” He long ago abandoned that view, but it’s a story line that presenters rarely resist when he’s introduced. “People always exaggerate that part of my past,” he shrugs.

Among other cataclysmic events, Balog has photographed the eruption of Mount St. Helens, the 2004 Indian Ocean tsunami, the aftermath of Hurricane Katrina, and the Deepwater Horizon oil spill. The scale of such events, and their impact on the human psyche, will always fascinate him. “We still carry this old caveman-imprint idea that we’re small, nature’s big, and it’s everything we can manage to hang on and survive,” Balog says. “When big geophysical events happen—a huge earthquake, tsunami, or volcanic eruption—we’re reminded of that.”

The push and pull between humans and the natural world is a theme in two of Balog’s best-known early projects. For his 1990 book, Survivors: A New Vision of Endangered Wildlife, he decided to shoot threatened species using the techniques of fashion photography. Each of the 62 animals in the book is treated as a star, photographed in front of intricately lit artificial backdrops. This style has often been mimicked since, but no one had seen anything like it at the time.

For 2004’s Tree: A New Vision of the American Forest, Balog spent six years photographing North America’s largest and oldest trees. At first he constructed elaborate portrait studios to photograph the bases of old-growth trees. Then he started scaling them, everything from huge oaks to sequoias and redwoods, shooting the giants in segments as he rappelled down. The resulting mosaics, which he painstakingly stitched together from hundreds of images, were innovative and powerful. Assessing Balog’s creations, photojournalist James Nachtwey says that “he makes us see, with both majesty and tenderness, the depth and tragedy of our loss unless we take action.”

As groundbreaking as Survivors and Tree were, neither has had the reach of Balog’s ice work. “It’s the biggest story on the planet, and Balog is at the forefront of it,” says Louie Psihoyos, executive director of the Oceanic Preservation Society and director of The Cove. In 2012, Balog formed a non-profit, Earth Vision Trust, to help tell this story through the media, education, and outreach. The idea, essentially, is to shock people into action, and his list of supporters includes people like Rahm Emanuel and Robert Redford. In 2009, Balog presented his findings to the White House Office of Energy and Climate Change Policy and also served as a NASA and State Department representative at the United Nations Climate Change Conference. “There are a lot of people talking about climate change,” says Psihoyos. “But when you’re talking about it, it’s like dancing on the radio. You can’t see it.”

While there are plenty of startling statistics in Chasing Ice, Balog’s quest “to show geological changes happening on a human time scale,” as he often puts it, drives the narrative. The film’s message is the same as 2006’s An Inconvenient Truth, but the style couldn’t be more different. Al Gore’s film was wonky and data driven; Orlowski lets adventure footage do the talking. An engine on a bush plane fails, dogsledding teams biff spectacularly, and four-season tents get shredded in gale-force winds. In one telling scene, Balog and his team repeatedly rappel into a moulin, a near vertical fissure in a glacier, on Greenland’s ice sheet. “Every night we’d look at the images in the tent,” Orlowski recalls, “and every night he’d say, ‘They’re not good enough.’ We spent four days there.”

Balog has demonstrated the same level of determination off-camera. For five years, he’s been continuously networking, lecturing, fundraising, and, of course, taking photographs and video. “I relate to him because he has risked it all,” says Will Steger, the polar adventurer and climate-change activist. “He has figured out a way to capture what no one else has been able to capture. And he has to show it to other people.”

Meanwhile, the mechanical robots, as Balog likes to call them, keep clicking away. Most of the original EIS cameras are still in the field, and over the past few years, in collaboration with various scientists and universities, the group has installed new ones on Devon Island, which sits high in the Arctic between Baffin and Ellesmere islands, and another pair on Greenland’s Petermann Glacier. Now Balog is thinking about taking EIS to the Andes. “For better or worse, there’s no end,” he says. “The cameras have to keep going indefinitely because of the power of the story.”

LAST JULY, I MET up with Balog once more, at the Aspen Ideas Festival, an event that one political writer dubbed “D.C.’s summer camp.” There are plenty of A-listers on the roster—including former Pakistani president Pervez Musharraf and former treasury secretary Lawrence Summers—but the atmosphere is more cushy than crackling. Colorado was in the midst of a record-breaking heat wave, and bowls of fresh fruit and jars of cucumber water were everywhere.

Balog has spoken at dozens of such conferences over the years, and his duties here are comparatively light: he’ll give a short talk and field a few questions after a screening of Chasing Ice. The audience gives Balog a standing ovation when he takes the stage—not as long as the deafening, minute-long one the film received at an earlier festival in Italy, but you can tell that people are moved by what they’ve just seen. They ask all kinds of questions but mostly just want to know what they can do.

There are no easy answers, of course. Onstage, Balog’s tone was positive, but his responses were about what you’d expect—check the renewable-energy box on your utility bill, drive a hybrid. Earlier he acknowledged that it would probably take a catastrophic event to move the behavioral needle. This was a few months before Hurricane Sandy hit, and only time will tell if that storm proved to be a turning point.

After the film, when the adrenaline surge of public speaking had worn off, Balog admitted that we might have already gone too far. “Maybe all we’re doing is preserving a moment in time for the historical record—here’s how it was, sorry we messed it up.”

Before Chasing Ice, Balog’s non-profit group, Earth Vision Trust, was struggling. Balog was exhausted and tired of fundraising, his least favorite part of the job. Then Sundance happened. The spike in donations allowed him to hire an executive director and a fundraising specialist. Although the group’s annual operating budget is still only $250,000, it’s growing, and EVT recently began creating curricula for teachers that can be accessed free online.

Balog was also excited about revisiting some of the themes of his earlier work. “Implicit in the tree project is the deforestation of North America,” Balog says, “but I didn’t hit that drum very hard.” Later I asked him if he was surprised by how politically taboo the topic of climate change had become. “I don’t give a shit what the political and financial guys are saying,” he says, slowing down his cadence and tapping fingers on the table in time with each word. “This is what’s true. And we’re going to speak the truth.”

The month of July turned out to be the hottest, and one of the driest, on record for the continental United States. By summer’s end, the belt of ice surrounding the Arctic had melted to its lowest level in recorded history, and crops were in such dire shape that the Department of Agriculture had designated nearly two-thirds of all U.S. counties disaster areas. In mid-July, a few weeks after Aspen Ideas, an iceberg measuring 46 square miles broke away from Greenland’s Petermann Glacier, creating headlines around the world. I called Balog to see if he thought his robots had caught the breakup on film.

He wasn’t sure. Operating in Greenland is absurdly expensive, he explained, and it had cost about $80,000 to get the cameras up there in the first place, much of that provided by a research grant from the University of Wales and Ohio State University that had since dried up. He figured it would cost about that much to go back and see if the cameras were still standing, let alone clicking away. Even so, he sounded as determined and philosophical as ever. “Serendipity got the cameras up there,” he said, “and serendipity will get us back. One way or the other, we’re going to get those images.”